I know this is not an answer to your ACR question, but I use Nikon Capture NX2 with excellent results. There is a free trial. I suggest stetting the camera's Picture Control set Normal to start. Unless you are shooting people, bump up the sharpness 3 or 4 steps. If you are in flat light, bump up the brightnesss setting. It only goes one step higher.

I will see if CS5 will take the D800 file and let you know. Have fun.Paul

If the lens is too heavy and there is no collar, it is always possible to use a long adapter plate tripod and make a cradle from a piece of Nylon (long term solution). Or just stick a twig between the lens and the plate, something we had to do when shooting video with 24-70mm Canon and the lens would always dip and raise when turning the follow focus ring. The nearest Oak tree came to rescue!

I've had no issues with the lens mount of the 14-24mm on my D800 or even my D700. It just seems like the camera will have issues, but so far since last March, and the year previous with the D700 experience says you'll be fine, even on a tripod.